In this topic, you study Shell Type Transformer.
Fig. 1 (a) shows the elementary scheme of a shell type transformer and Fig. 1 (b) shows the shell type transformer as used in actual practice.
Fig. 1: Shell type transformer
Distinguishing Features
Some of the specialties of the shell type transformer are listed below
- The core of this type of transformer provides double magnetic circuit.
- The windings are normally sandwich type, always placed on the central limb of the core. H.V. and L V. coils which are wound in the form of pancakes, are interleaved. The top and bottom coils which are near the yoke of the core, are of L. V. winding only.
- The core nearly surrounds the windings placed on the central limb of the core. This feature is useful from the point of view of providing mechanical protection to the windings.
- Since the coils are placed on one limb (central) only and are surrounded by the core, natural cooling is poor.
- When the coils are to be withdrawn for repairs, large number of laminations are to be dismantled.